Cycloidal ship propeller



Dec. 28, 1965 BU CKLE ETAL 3,225,834

(JYGLOIDAL SHIP PROPELLER Filed Nov. 14, 1962 INVENTOR Kart Buckle Eugen Hz'z'H/ch Wilhelm Hub United States Patent 3,225,834 CYCLOIDAL SHIP PROIELLER Karl Blickle, Bolheim, Eugen Hiitlich, Heidenheim, and Wilhelm Huh, Saarbrucken, Germany, assignors to J. M. Voith G.m.b.H., Heidenheim, Germany Filed Nov. 14, 1962, Ser. No. 239,866 2 Claims. (Cl. 170-148) The present invention relates to a cycloidal ship propeller with a blade wheel body rotatably journalled in the ship body, in which a plurality of at least nearly axis parallel blades are pivotally mounted in said blade wheel body while said blades are uniformly distributed along a circle coaxial with the axis of rotation of said rotatable blade wheel body. For purposes of controlling the oscillating movement of the blades about a tangential central position, the individual blades are through a blade actuating linkage system, a so-called kinematic, connected to a control center or control disc which is common to all blades and is operable from the outside of the blade wheel body. The blade actuating linkage includes at least one lever which may also be termed blade lever and is operatively connected to the blade pivot, and also includes a connecting rod linked to said lever, and furthermore includes a double lever pivotally connected to the blade wheel body while one end of said double lever is connected to the connecting rod whereas the other end of said double lever is connected to the control disc.

With ships having a plurality, for instance two adjacent simultaneously operated cycloidal propellers, it is when moving straight ahead necessary for the purpose of torque compensation to cause two propellers to rotate in opposite direction with regard to each other. When employing heretofore known blade actuating linkages as set forth for instance in US. Patent No. 2,978,036, the above mentioned step namely to have the two propellers rotated in opposite direction to each other has the drawback that the blade wheel body and the blade actuating linkage has to be designed once for a propeller rotating in clockwise direction and another time for a propeller rotating in counterclockwise direction. This in turn means that for producing clockwise rotating propellers other machine shop drawings, other models, devices and similar manufacturing aids have to be produced than is necessary for counterclockwise moving propellers so that the cost for the manufacture and the stockkeeping of the propellers is considerably increased.

It is, therefore, an object of the present invention to provide a cycloidal ship propeller, which will overcome the above mentioned drawbacks.

It is another object of this invention to provide a cycloidal sh-ip propeller and in particular the blade actuating linkage system in such a way that the same type of blade wheel body may be employed for propellers rotating in clockwise direction and for propellers rotating in counterclockwise direction.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIGS. 1, 2 and 3 diagrammatically illustrate three embodiments of a cycloidal ship propeller with a blade actuating linkage system according to the present invention.

FIG. 4 is a view showing the propeller of FIG. 1 with four actuating linkage systems according to the invention and with the control disc for said linkage system shifted off-center with regard to its position shown in FIG. 1.

GENERAL ARRANGEMENT In order to overcome the drawbacks outlined above with heretofore known linkage systems for cycloidal ship propellers, according to the present invent-ion, the axis of the pivot by means of which the two-arm lever of the blade actuating linkage system is linked to the blade wheel body is arranged in a radial plane defined by the axis of rotation of the blade wheel body and the pivot axis of the respective blade actuated by said blade actuating linkage system.

A blade actuating linkage system designed in this way makes it possible to produce one and the same type blade wheel body for propellers rotating in clockwise direction as well as for propellers rotating in counter-clockwise direction. Thus, instead of providing two blade wheel bodies as was heretofore necessary, when employing a blade wheel linkage system according to the invention, only one type of blade wheel body is necessary so that the costs for keeping stock and replacement parts will be greatly reduced and the replacement of the parts will be greatly simplified.

STRUCTURAL ARRANGEMENT Referring now to the drawings in detail, it should be noted that the blades are illustrated in their tangential central position, i.e. in a position in which the longitudinal central plane of each blade is tangential to the circle on which the pivot axes of said blades are located.

As will be seen from the various figures in the drawings in which the same elements have been designated with the same reference numerals, in the blade Wheel body 1 of the cycloidal propeller, which blade wheel body is rotatably journalled in the ship body, there is provided a control disc 3 common to all of the blades 2 and operable from the outside of the blade wheel body. In addition thereto, within said rotatable blade wheel body 1 there is provided a number of blade actuating linkage systems corresponding to the number of the blades with which the blade wheel body is equipped. For purposes of clarity, however, each of the various FIGS. 1 to 3 illustrates one blade wheel actuating linkage system only.

As will be seen from the drawings, each blade actuating linkage system has a pivot 4 connected to control disc 3 in spaced relationship to the center 11 thereof. The linkage system also comprises a two-arm lever 7a which on one hand is pivotally connected to pivot 4 and on the other hand is pivotally connected to a connecting rod 5 and which is furthermore by means of a fiat link 7b and a pivot 6 pivotally connected to the blade wheel body 7. Each blade wheel actuating linkage system furthermore comprises a blade wheel lever 8. The axis of the pivot 6 mounted on the blade wheel body 1 is located in the radial plane 10 defined by the axis of rotation 11 of the blade wheel body 1 and the pivot axis 12 of the respective blade 2 pertaining thereto.

It will be appreciated that if control disc 3 has been moved out of its central position for instance by a control stick in the center of the control disc, a controlled oscillating movement about the tangential central position of blades 2 will be imparted upon said blades through the intervention of the control disc 3. In the tangential central position, the profile chord is tangent to the blade circle 9.

In order with a cycloidal ship propeller according to the present invention to obtain a more favorable adjustment of the angle between the profile chord 13 of blades 2 and the tangent to the blade wheel circle 9, in other words in order to obtain a more favorable course of the so-called blade angle curve and thereby favorable degrees of efliciency of the propeller, and also to obtain a better lubrication of the individual joints of the blade driving linkage system, the blade wheel actuating linkage system is according to the embodiment shown in FIGS. 1 and 2 so designed that the lever arms of the two-arm lever linked by a flat link to the blade wheel body confine on the side of the link pivot an angle of 170 while the lever arms are located on one and the same side of the radial plane 10. According to a further development of the invention, as shown in FIG. 2; the ratio of the length of the lever arm 12 connected to the control disc to the length of the lever arm a connected to the connecting rod is about 1.2: 1. Also with a blade wheel actuating linkage system with a two-arm lever confining anangle of 180 therebetween, as shown in FIG. 3, the same ratio of the lever arms of the two-arm lever is advantageous.

By appropriately selecting the angles and/or the lever arm lengths of the two-arm lever it is possible to adjust the blade pitch to more favorable values than was possible with heretofore known designs of blade wheel actuating linkage systems, so that with the present invention better degrees of eificiency of the propeller can be obtained than were heretofore possible. Furthermore, by an appropriate design of the blade wheel actuating linkage system according to the present invention, there will be obtained the advantage that the torques acting on the control disc and varying several times from positive to negative peaks during a rotation of the propeller and movement of the control center out of its central position, will have approximately the same magnitude. Con sequently, the peaks of the reciprocating forces in the individual joints of the kinematics will be reduced while simultaneously a more favorable lubrication will be obtained than was heretofore obtainable.

In FIG. 4 a cycloidal propeller is shown with the control disc 3 shifted off-center so that the position of the four propeller blades A, B, C and D in the four quadrants will be seen.

The center point of the control disc 3 is displaced on the transverse diameter from the center point of the blade wheel body 1 by a distance 2 toward the left. This displacement corresponds to a direction of attack of the force of the water on the propeller and thereby a direction of advancement of the propeller and of the ship in upward direction, with regard to the drawing, as shown by arrow p. In positions A, C of the propeller blade in which the pivot axis 12 of the blade coincides with the point of intersection of the transverse diameter with the blade wheel orbit 9, the blade is tangential to the blade wheel orbit as was the case before. In the two other positions B, D which correspond to an advancing movement of the blade on the blade wheel orbit by 90 or 270, respectively, with respect to the blade position A, the blades are tilted out of the tangential position, in such a way that the head of the blade at the top of the view is tilted outwardly and at the bottom of the view the head of the blade is tilted toward the inside. That blade which is designated A is, after a rotation of the wheel body in the direction of the arrow q of 90, in the position of the blade B, after a further rotation of 90, it has reached the position of the blade C and is again in a tangential position and, finally, after a further rotation of 90 (270 from the starting position) it has reached the position of the blade D.

It is, of course, to be understood that the present invention is, by no means, limited to the particular constructions shown in the drawings but also comprises any modifications within the scope of the appended claims.

What we claim is:

1. A cycloidal ship propeller comprising: a blade wheel body rotatable on a central axis, a plurality of blades pivotally supported by said blade wheel body and having their pivot axes arranged along a circle concentric with said blade wheel central axis and in substantially uniformly spaced relationship to each other, said pivot axes being substantially parallel to each other and also parallel to said central axis, each of said blades being capable of an oscillating movement about its pivot axis, adjustable control means common to all of said blades and movable selectively from a central position coaxial with said central axis of said blade wheel body into any one of a plurality of positions eccentric with regard to said central axis of said blade wheel body and vice versa to govern the oscillating movement of said blades, each of said blades comprising a pivot and being oscillatable about a middle position of the blade in which the respective blade is tangential to the circle along which the pivot axes of said blades are arranged, a plurality of blade actuating linkage systems respectively operatively connecting said adjustable control means with said blades so that each of said blades will be operable in response to a rotation of said wheel body and while said adjustable control means occupies any of its possible positions to carry out an oscillating movementhaving the predetermined magnitude of the blade angles which correspond to the respective circular positions of the pivot axes of the blades during their circular movement with said blade wheel body, each of said blade actuating linkage systems comprising at least one lever operatively connected to the respective blade pivot and also comprising a connecting rod linked to said lever, each of said blade actuating linkage systems furthermore comprising a two-arm lever having one of its arms connected to said connecting rod and having its other arm linked to said adjustable control means in spaced relationship to the center thereof, a link having one end pivoted to said two-arm lever in the region of the junction of the two arms thereof and the other end pivoted to a point on said wheel body, said point on the wheel body being located-in a radial plane passing through the axis of rotation of said wheel body and through the axis of the pivotal connection of the respective blade with said blade wheel body and also being located between said axes, the arrangement being such that for each blade and the linkage system pertaining thereto, with regard to the direction of rotation of said wheel body, the lever and rod and at least that arm of the two-arm lever which is linked to said rod, all pertaining to said blade actuating linkage system, in the central position of said control means are located behind said radial plane, the two arms of said two-arm lever forming with each other an angle of approximately and said angle being located on the same side of said two-arm lever as said link.

2. A cycloidal ship propeller comprising: a blade wheel body rotatable on a central axis, a plurality of blades pivotally supported by said blade wheel body and having their pivot axes arranged along a circle concentric with said blade wheel central axis and in substantially uniformly spaced relationship to each other, said pivot axes being substantially parallel to each other and also parallel to said central axis, each of said blades being capable of an oscillating movement about its pivot axis, adjustable control means common to all of said blades and movable selectively from a central position coaxial with said central axis of said blade wheel body into any one of a plurality of positions eccentric with regard to said central axis of said blade wheel body and vice versa to govern the oscillating movement of said blades, each of said blades comprising a pivot and being oscillatable about a middle position of the blade in which the respective blade is tangential to the circle along which the pivot axes of said blades are arranged, a plurality of blade actuating linkage systems respectively operatively connecting said adjustable control means with said blades so that each of said blades will be operable in response to a rotation of said wheel body and while said adjustable control means occupies any of its possible positions to carry out an oscillating movement having the predetermined magnitude of the blade angles which correspond to the respective circular positions of the pivot axes of the blades during their circular movement with said blade wheel body, each of said blade actuating linkage systems comprising at least one lever operatively connected to the respective blade pivot and also comprising a connecting rod linked to said lever, each of said blade actuating linkage systems furthermore comprising a two-arm lever having one of its arms connected to said connecting rod and having its other arm linked to said adjustable control means in spaced relationship to the center thereof, a link having one end pivoted to said two-arm lever in the region of the junction of the two arms thereof and the other end pivoted to a point on said wheel body, said point on the wheel body being located in a radial plane passing through the axis of rotation of said wheel body and through the axis of the pivotal connection of the respective blade with said blade wheel body and also being located between said axes, the arrangement being such that for each blade and the linkage system pertaining thereto, with regard to the direction of rotation of said wheel body, the lever and rod and at least that arm of the two-arm lever which is linked to said rod, all pertaining to said blade actuating linkage system, in the central position of said control means, are located behind said radial plane, the ratio of the length of that arm of said two-arm lever which is connected to said adjustable 6 control means to the length of the other arm of said two-arm lever being 1211.

References Cited by the Examiner UNITED STATES PATENTS MARK NEWMAN, Primary Examiner.

MILTON BUCHLER, ABRAM BLUM, JULIUS E.

WEST, Examiners. 

1. A CYCLOIDAL SHIP PROPELLER COMPRISING: A BLADE WHEEL BODY ROTATABLE ON A CENTRAL AXIS, A PLURALITY OF BLADES PIVOTALY SUPPORTED BY SAID BLADE WHEEL BODY AND HAVING THEIR PIVOT AXES ARRANGED ALONG A CIRCLE CONCENTRIC WITH SAID BLADE WHEEL CENTRA AXIS AND IN SUBSTANTIALLY UNIFORMLY SPACED RELATIONSHIP TO EACH OTHER, SAID PIVOT AXES BEING SUBSTANTIALLY PARALLEL TO EACH OTHER AND ALSO PARALLEL TO SAID CENTRAL AXIS, EACH OF SAID BLADES BEING CAPABLE ABLE CONTROL MEANS COMMON TO ALL OF SAID BLADES AND MOVABLE SELECTIVELY FROM A CENTRAL POSITION COAXIAL WITH SAID CENTRAL AXIS OF SAID BLADE WHEEL BODY INTO ANY ONE OF A PLURALITY OF POSITIONS ECCENTRIC WITH REGARD TO SAID OF A PLURALITY OF POSITIONS ECCENTRIC WITH REGARD TO SAID CENTRAL AXIS OF SAID BLADE WHEEL BODY AND VICE VERSA TO GOVERN THE OSCILLATING MOVEMENT OF SAID BLADES, EACH OF SAID BLADES COMPRISING A PIVOT AND BEING OSCILLATABLE ABOUT A MIDDLE POSITION OF THE BLADE IN WHICH THE RESPECTIVE BLADE IS TANGENTIAL TO THE CIRCLE ALONG WHICH THE PIVOT AXES OF SAID BLADES ARE ARRANGED, A PLURALITY OF BLADE ACTUATING LINKAGE SYSTEMS RESPECTIVELY OPERATIVELY CONNECTING SAID ADJUSTABLE CONTROL MEANS WITH SAID BLADES SO THAT EACH OF SAID BLADES WILL BE OPERABLE IN RESPONSE TO ROTATION OF SAID WHEEL BODY AND WHILE SAID ADJUSTABLE CONTROL MEANS OCCUPIES ANY OF ITS POSSIBLE POSITIONS TO CARRY OUT AN OSCILLATING MOVEMENT HAVING THE PREDETERMINED MAGNITUDE OF THE BLADE ANGLES WHICH CORRESPOND TO THE RESPECTIVE CIRCULAR POSITIONS OF THE PIVOT AXES OF THE BLADES OF DURING THEIR CIRCULAR MOVEMENT WITH SAID BLADE WHEEL BODY, EACH OF SAID BLADE ACTUATING LINKAGE SYSTEMS COMPRISING AT LEST ONE LEVER OPERATIVELY CONNECTED TO THE RESPECTIVE BLADE PIVOT AND ALSO COMPRISING A CONNECTING ROD LINKED TO SAID LEVER, EACH OF SAID BLADE ACTUATING LINKAGE SYSTEMS FURTHERMORE COMPRISING A TWO-ARM LEVER HAVING ONE OF ITS ARMS CONNECTED TO SAID CONNECTING ROD AND HAVING ITS OTHER ARM LINKED TO SAID ADJUSTABLE CONTROL MEANS IN SPACED RELATIONSHIP TO THE CENTER THEREOF, A LINK HAVING ONE END PIVOTED TO SID TWO-ARM LEVER IN THE REGION OF THE JUNCTION OF THE TWO ARMS THEREOF AND THE OTHER END PIVOTED TO A POINT ON SAID WHEEL BODY, SAID POINT ON THE WHEEL BODY BEING LOCATED IN A RADIAL PLANE PASSING THROUGH THE AXIS OF THE PIVOTAL CONNECTION OF THE AND THROUGH THE AXIS OF THE PIVOTAL CONNECTION OF THE RESPECTIVE BLADE WITH SAID BLADE WHEEL BODY AND ALSO BEING LOCATED BETWEEN SAID AXES, THE ARRANGEMENT BEING SUCH THAT FOR EACH BLADE AND THE LINKAGE SYSTEM PERTAINING THERETO, WITH REGARD TO THE DIRECTION OF ROTATION OF SAID WHEEL BODY, THE LVER AND ROD AND AT LEAST THAT ARM OF THE TWO-ARM LEVER AND ROD AND AT LEAST THAT ALL PERTAINING TO SAID BLADE ACTUATING LINKAGE SYSTEM, IN THE CENTRAL POSITION OF SIAD CONTROL MEANS ARE LOCATED BEHIND SAID RADIAL PLANE, THE TWO ARMS OF SAID TWO-ARM LEVER FORMING WITH EACH OTHER AN ANGLE OF APPROXIMATELY 170*, AND SAID ANGLE BEING LOCATED ON THE SAME SIDE OF SAID TWO-ARM LEVER AS SAID LINK. 